JPS6143979B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a live feed composition for fish farming. More specifically, thiamin or thiamin salts are coated with a coating agent consisting of oil, lecithin, and polyglycerol polymerized fatty acid ester with a melting point of 50 to 80°C in an amount of 1/3 to 1 times the amount of thiamin or thiamine salts in live feed for fish farming. The present invention relates to a live fish feed composition containing thiamine salts. With the development of marine fish aquaculture in Japan, various compound feeds have been developed, but live feed is still used for the most part. In particular, for yellowtail, which accounts for the majority of marine aquaculture production, the use of artificial compound feed is minimal, and only in very limited cases, such as when it is difficult to prepare live feed or when treating disease. Therefore, securing and storing live feed is a major concern for marine aquaculture farmers. The live bait currently used for culturing yellowtail, red sea bream, etc. is fresh or frozen fish, and the types include sand eel, anchovy, horse mackerel, mackerel, saury, and sardine. Raw bait tends to lose its freshness. It goes without saying that feeding raw food that is not fresh can have a negative impact on fish, but with advances in freezing technology today, there is no need to worry so much. An incident in which a large number of young yellowtail yellowtails died when anchovies were administered continuously led to various experimental studies to investigate the cause, and it was discovered that thiamin deficiency was the cause. This thiamin deficiency is caused by the decomposition of thiamin in the anchovy body by thiaminase in living tissues due to preservation of raw food or exposure to thiamin. Thiamin is also essential in fish.
When thiamin-deficient feed is administered, deficiency symptoms appear in each cultured fish. Symptoms vary depending on the species of fish, and in the case of yellowtail, symptoms such as loss of appetite, black discoloration, loss of balance, etc. occur, and the fish die. The mass mortality of yellowtail caused by a lack of thiamine threatens the economic base of yellowtail farmers, and is a matter of life and death for yellowtail farmers. Anchovies are not the only fish that contain thiaminase in their bodies. Table 1 shows the distribution of thiaminase in marine fish. Very strong thiaminase exists in anchovies and saury, which have a relatively stable catch and are used as live feed for aquaculture, and also in sand locusts. Apart from anchovies, sand eel, and saury, there are currently no other fish species that can be used as live bait for yellowtail farming.

[Table] When rearing yellowtail with anchovies or saury, it is said to be safe to administer thiamine nitrate at a dose of 5 mg per 1 kg of fish weight per day to prevent thiamine deficiency. However, even if thiamin is added and administered to live feed that contains thiaminase, thiamin is rapidly decomposed by thiaminase, so it is necessary to administer an extremely large amount, which increases the economic burden on yellowtail farmers. Furthermore, if it takes a long time to administer the food after feeding, there may be no thiamine left at all. As a measure to solve such problems,
A method described in Publication No. -13192 has been proposed. The invention described in the above publication is characterized in that the live feed for fish farming contains thiamin or thiamin salts with a particle size of 100 to 1000μ coated with 1 to 10 times the amount of higher fatty acid or glycerin fatty acid ester. It is also stated that according to the present invention, thiamine or its salts do not elute even in minced fish meat, thereby preventing thiamine deficiency from occurring in raw feed. As a method for obtaining coated granules of thiamin or thiamin salts of the present invention, for example, hydrogenated beef tallow oil melted in thiamine hydrochloride powder at around 60 to 70°C is added to thiamin hydrochloride in a ratio of 1.
Add ~10 times the amount, preferably about 4 times the amount, mix with a homogenizer, and spray the mixture with a rotating disc type sprayer for 30 minutes.
Spray into a room adjusted to below ℃, particle size 100 ~
A method is described to obtain a 1000μ powder formulation. In this case, it is said that thiamine hydrochloride is preferably pulverized to about 1 to 10 microns.
In addition, if the ratio of the coating agent to thiamine is less than 1, sufficient coating will not be achieved.For example, if the coating agent:thiamine hydrochloride ratio is 0.8:1.0, almost no coating effect will be observed even if the average particle size is 200μ. When this material was mixed with minced anchovies as thiamin at a ratio of 10 mg/100 g and kept at 30°C for 1 hour, the remaining amount was measured, and the residual rate was very small.
It has been pointed out that it was 4.5%. The average particle size of commercially available general thiamine or thiamine hydrochloric acids is often about 50 μm, which is much larger than the particle size required by the above-mentioned publication.
It is not an easy task to pulverize approximately 50 microns to about 1 to 10 microns, and it would be desirable to use commercially available thiamine or thiamine salts as they are to make coated particles. However, coated grains prototyped using unpulverized thiamine salts according to the conditions of the above publication were
Compared to coated grains of thiamin salts ground to 10μ,
The residual amount in minced fish meat showed extremely poor results. In addition, the content of thiamin salt-coated grains prepared with 1 to 10 times the amount of coating agent is 50% as thiamin salt.
This means ~9.09%. It goes without saying that the amount of hydrogenated beef tallow oil used in the coating should be as small as possible, considering the processing costs of the coated grains and the burden of digestion and absorption by fish. The purpose of the present invention is to provide coated particles of thiamine or thiamine salts that satisfy the above requirements, and more specifically, to provide coated particles of thiamine or thiamine salts with an average particle size of 50μ. The purpose is to provide coated granules of thiamin or thiamin salts with a thiamin content of 50% or more, as high as possible, using the finely pulverized product (average particle size 5μ), and is used in live feed for fish farming. Oils and fats with a melting point of 50 to 80°C in an amount of 1 times or less and 1/3 times or more of thiamine or thiamine salts,
The present invention relates to a live fish feed composition containing thiamine or thiamin salts coated with a coating agent consisting of a combination of lecithin and polyglycerol polymerized fatty acid ester in a certain ratio. In the present invention, thiamine salts refer to thiamine nitrates, hydrochlorides, thiocyanates, and the like. As the fats and oils having a melting point of 50 to 80°C that can be used in the coating composition suitable for the purpose of the present invention, waxes, waxes, hardened oils, higher fatty acids, etc. can be used, but hardened oils are particularly suitable. As hydrogenated oil,
For example, hydrogenated beef tallow oil, hydrogenated pork fat oil, hydrogenated chicken fat oil,
Examples include hydrogenated animal oils such as hydrogenated whale oil and hydrogenated fish oil, and hydrogenated vegetable oils such as hydrogenated soybean oil, hydrogenated rapeseed oil, hydrogenated palm oil, and hydrogenated coconut oil. These can be used alone or in combination of two or more. Among the properties that a coating composition must have, the target content of thiamine or thiamine salts is as high as 50% or more, so a molten mixture of thiamine or thiamine hydrochloride as a core material and the coating composition is required. The viscosity should be such that it can be uniformly and effectively sprayed and dispersed by a suitable atomizing device such as a rotating disk type atomizing device or a spray nozzle. It is not possible to achieve this viscosity by using the hydrogenated oil alone, and for this purpose an emulsifier consisting of a combination of lecithin and polyglycerol polymerized fatty acid ester is added to the hydrogenated oil. Test Example 1 conducted for the purpose of searching for an emulsifier that is effective in reducing the viscosity of a molten mixture of hardened oil and thiamine or thiamine salts will be shown, and the usefulness of the present invention will be explained. Test Example-1 A heated molten suspension was prepared using thiamine nitrate (pulverized product with an average particle size of 4μ) as a thiamine salt, hydrogenated tallow oil (melting point 59.5°C) as a hydrogenated oil, and various emulsifiers, and heated to 75°C. The viscosity of each suspension was measured using a B-type viscometer manufactured by Tokyo Keiki Seisakusho Co., Ltd. The composition of the suspension was 60 parts of thiamine nitrate powder, 40 parts of hardened beef tallow oil, and the amount of various emulsifiers was 2 parts. The results obtained are shown in Table 2.

[Table] As can be seen from the results, the emulsifiers that clearly contribute to lowering the viscosity of the suspension are lecithin and polyglycerin polyricinolate (hereinafter abbreviated as PGPR), but when these emulsifiers are used alone, the viscosity of the suspension decreases. is still quite high and is not necessarily suitable for the purpose of further increasing the content of thiamine nitrate. Next, with the lecithin that was effective in Test Example-1,
Test Example 2 shows the results of looking at the effect of combining PGPR. Test Example-2 The test conditions were the same as Test Example-1. The composition of the suspension was 60 parts of thiamine nitrate powder, 40 parts of hardened beef tallow oil, and the amounts of lecithin and PGPR added and the results are shown in Table 3.

[Table] As shown in the results, in the case of a system containing 60 parts of thiamine nitrate and 40 parts of hardened beef tallow, if lecithin is used in combination with 1 part or 2 parts of PGPR within the range of 1/10 or 1/2 of PGPR, there is a problem. The viscosity of the suspension is rapidly decreasing. The reason for this is currently unknown, but since such a reduction in viscosity has not been achieved by using PGPR or lecithin alone, it seems that some synergistic effect is exerted by the combination. The present invention was completed by utilizing the above knowledge, and according to the present invention, it is possible to easily produce granules coated with thiamine or thiamine salts with a high content, which was impossible by the method disclosed in Japanese Patent Publication No. 50-13192. It will be possible. As the thiamin used in the present invention, soybean phospholipid produced as a by-product during soybean oil refining is suitable in terms of cost and performance, but egg yolk lecithin separated and purified from egg yolk can also be used. In the present invention, the polyglycerol polymerized fatty acid ester is an ester of polyglycerin with an average degree of polymerization of 2 to 5 and a fatty acid polymer with an average degree of polymerization of 3 to 8. Acids or castor oil fatty acids containing these fatty acids are preferred. All of these polyglycerol polymerized fatty acid esters are highly viscous liquids that are insoluble in water, ethanol, and oils and fats.
Soluble in ether. The amounts of lecithin and polyglycerol polymerized fatty acid ester in a composition comprising a combination of oil or fat, lecithin, and polyglycerol polymerized fatty acid ester used as a coating agent are limited by the melting point of the oil or fat. Both lecithin and polyglycerol polymerized fatty acid ester do not form a solid state at room temperature, and if the amount of these added is extremely large, the strength of the coating film will become undesirable. When hydrogenated beef tallow oil (melting point 59.6°C) is used as the fat, if polyglycerol fatty acid ester and lecithin are used together, the amount of polyglycerol fatty acid ester will be 1.0 parts per 100 parts of hydrogenated beef tallow oil.
The amount of lecithin is 15 parts, preferably 2.5 to 10 parts, and the appropriate amount of lecithin is 1/20 to 1 times the amount of polyglycerol polymerized fatty acid ester. Examples of methods for coating thiamine or thiamine salt powder with the coating agent of the present invention include the following method, but the present invention is not limited thereto. 28.5 parts of hardened beef tallow oil, 1 part of polyglycerol polymerized fatty acid ester, and 0.5 part of lecithin at 65-75%
Gradually add 70 parts of thiamine nitrate fine powder (average particle size 5μ) to the mixture melted at around ℃ and mix. Add the entire amount of thiamin nitrate fine powder while maintaining the temperature of the suspension at around 65 to 75°C, mix uniformly, and spray it into a room adjusted to below 30°C using a rotating disc type sprayer. Encapsulated particles of thiamine nitrate with a diameter of 100 to 1000 μ are obtained. When supplying the suspension to the rotating disc type spray device, it is also possible, if necessary, to pump the suspension at a suitable pressure. It is extremely difficult to reduce the particle size of coated particles to 100μ or less, considering the viscosity of the suspension.
Further, if the particle size is 1000μ or more, there is no problem in producing coated grains, but if the particle size is too large and mixed into minced meat, uniform dispersion is difficult and the effect tends to vary. From this point of view, it can be said that the particle diameter of the coated particles of thiamine or thiamine salts is preferably 100 to 1000 μm. According to the method of the present invention, a good coating effect can be obtained even when the ratio of the coating agent to thiamine or thiamine salts is much less than 1, and in this point, the effect is significantly different from the method according to Japanese Patent Publication No. 13192/1983. It is. For example, in Japanese Patent Publication No. 50-13192, when the ratio of coating agent: thiamine hydrochloride is 0.8:1.0, the average particle size is
Even when a 200 μm product was made, there was almost no coating effect, so this product was mixed with minced anchovies as thiamin at a ratio of 10 mg/100 g and heated at 30°C.
It is stated that when the residual amount was measured after being kept warm for 1 hour, the residual rate was only 4.5%.The present inventors also used thiamin nitrate as the core material and hydrogenated tallow oil as the coating material, and the coating material : Thiamine nitrate was 0.8:1.0, and the residual rate of thiamin in minced saury was measured in exactly the same manner as in the method of Japanese Patent Publication No. 13192/1982, and the result was 47.3%. On the other hand, in the coating material of the present invention, when the coating material: thiamine nitrate (average particle size 50μ) is 0.43:1.00,
The residual rate of thiamine under the same conditions as above is 77.8
%, and the ratio of coating agent to thiamine is approximately 1/1.
Even though it is reduced to 2, the coating effect is actually improved. Next, Test Example 3 is shown as a specific example in which the particle size of thiamin or thiamin salts used as a core material has a large effect on the residual rate of thiamin when coated grains are added and mixed into minced fish containing thiaminase. . Test Example-3 28.5 parts of hydrogenated chicken fat oil (melting point 60℃) and 1 part of hydrogenated chicken fat oil (melting point 60℃)
Using a coating agent consisting of lecithin containing 0.5 parts of PGPR and 70 parts each of commercially available thiamin nitrate powder (vitamin B ₁ from Takeda Pharmaceutical Company Limited) with an average particle size of 50 μm or its fine powder with an average particle size of 4 μm, the core material was coated. Two products of thiamine nitrate coated grains having different particle sizes (each having a thiamine nitrate content of 70% and an average particle size of 300 μm) were produced. In order to investigate the decomposition rate of thiamin over time in minced saury, the coated grains of the above two products and commercially available thiamine nitrate powder were each added to minced saury at a concentration of 10 mg/100 g of thiamin, and the mixture was heated at 30°C. The remaining rate of thiamin was measured by leaving the sample under the same condition. The results are shown in Table 4.

[Table] The results show that uncoated thiamine nitrate is rapidly decomposed in minced saury, whereas decomposition of thiamine nitrate coated with the coating agent of the present invention is significantly prevented, especially thiamin nitrate finely ground to an average particle size of 5μ. Those coated with showed good results. When 70 parts of thiamine nitrate is added and mixed with 30 parts of hardened beef fat and the product temperature is maintained at 65 to 75°C, when the average particle size of thiamine nitrate is 50μ, fluidity is poor and the average particle size is At 5μ, the fluidity becomes extremely poor and a uniform spray condition cannot be expected at all. On the other hand, in the case of the coating material of the present invention, the viscosity of the suspension at 75°C is 2800CP even in the case of thiamine nitrate with an average particle size of 5μ, and a uniform spray state can be obtained by the rotating disc type spray device, and the coated particles can be No problems were observed during manufacturing. The effectiveness of the present invention will be explained in detail in Examples below. Example: Twenty-five yellowtail fish weighing an average of 100 g were divided into two groups, and each group was housed in a 2-ton rectangular concrete aquarium and raised at a water temperature of 22 to 24°C. The seawater in the aquarium is
We poured enough water into the aquarium to replace it 10 to 12 times, and extracted the corresponding amount of seawater from the bottom of the tank. Before entering the main experiment, after preliminarily rearing mainly horse mackerel for one week, the test plot was given 28.5 parts of hydrogenated beef tallow oil,
A coating composition consisting of 1 part PGPR and 0.5 part lecithin contains 70 parts thiamine nitrate powder (average particle size).
Thiamine nitrate-coated grains (containing 70% as thiamine nitrate) with a particle diameter of 300 to 500μ (50μ) were mixed at a ratio of 10mg of thiamine nitrate to 100g of minced anchovy at 10 a.m. and 3 p.m. The animals were fed twice a day, 325 g each time, for a total of 650 g. The control group was fed minced anchovies that did not contain thiamine nitrate. The test continued for 4 weeks by feeding anchovies, measuring the weight and number of dead fish in each group, measuring the amount of pyruvate in the blood, and observing changes in the liver (for a random number of 10 fish). The results are shown in Table 5.

【table】

[Table] As shown above, the experimental plot showed better results than the control plot in terms of fish weight, number of deaths, amount of pyruvate in the blood, and number of green liver cases. Additionally, many yellowtails in the control area were observed exhibiting abnormal behavior during rearing. From these facts, the effectiveness of the present invention was confirmed.

Claims (1)

[Claims] 1 Thiamin or thiamin salts coated with a coating agent consisting of oil with a melting point of 50 to 80°C, lecithin, and polyglycerol polymerized fatty acid ester in an amount of 1/3 to 1 times the amount of thiamin or thiamin salts in live feed for fish farming. 1. A live feed composition for fish farming, characterized by containing the following.